1. Field of the Disclosure
The present application relates to a liquid crystal display device and a driving method thereof, and more particularly to a liquid crystal display device and a driving method that are adapted to enhance picture quality.
2. Description of the Related Art
The liquid crystal display device includes a liquid crystal panel which is configured with a thin film transistor substrate provided with a plurality of thin film transistors and a color filter substrate provided with a color filter layer. The liquid crystal panel further includes a liquid crystal layer interposed between the two substrates.
In general, almost all the liquid crystal display devices include the color filter layer, which is formed on the color filter substrate and configured with three primary colored filters such as red, green and blue filter. The liquid crystal display devices control the quantity of light transmitted through the color filter layer and display a desired color.
Recently, a display technology of red, green, blue and white (hereinafter, “RGBW”) mode has been developed which further includes white besides red, green and blue, in order to enhance brightness. As such, a method of deriving four color voltages from three color data, rendering methods and so on are applied to the driving of the liquid crystal panel.
The rendering methods individually drive pixels and simultaneously drive pixels adjacent to the pixel to be driven. In other words, the rendering method disperses brightness to the adjacent pixels and displays a single dot.
Among the rendering methods, a sub-pixel rendering method is being used as a technology capable of realize a high definition display using the small number of display pixels. The sub-pixel rendering method enables a gray signal applied to a sub-pixel of a display pixel with an arbitrary color to be overlapped with other sub-pixels adjacent to the display pixel, in order to display an image.
Such a sub-pixel rendering method can reduce the number of sub-pixels within a red, green and blue stripe arrangement to 3/2. In this case, the sub-pixel rendering method can provide the same definition as that of the red, green and blue stripe arrangement according to the related art. As the number of sub-pixels decreases, the area of each sub-pixel can be expanded to 3/2 times. Therefore, the sub-pixel rendering method can allow each sub-pixel to have a high aperture ratio.
The sub-pixel rendering method is also applied to a liquid crystal display device which has a red, green, blue and white stripe arrangement instead of the red, green and blue stripe arrangement. In the liquid crystal display device with the red, green, blue and white stripe arrangement, red, green, blue and white sub-pixels or color filters are arranged in stripe shapes.
The liquid crystal display device with the red, green, blue and white stripe arrangement converts received red, green and blue data into red, green, blue and white data and applies the above-mentioned sub-pixel rendering method to the red, green, blue and white data, in order to display an image. In this case, the sub-pixel rendering method enhances the definition of the liquid crystal display device.
However, the distance between the same color sub-pixels being physically alternated in the red, green, blue and white stripe arrangement is lengthened by ¾ compared to the red, green and blue stripe arrangement of the related art. Also, the same color sub-pixels are arranged adjacently to one another in a vertical direction. As such, not only the definition deteriorates but also a line dim appears on the screen, even though the sub-pixel rendering method is applied to the liquid crystal display device with the red, green, blue and white stripe arrangement. Due to this, picture quality can deteriorate.